Regarding the April 17 editorial, "Obama's too cool on gun restrictions": A major problem with the assault weapons ban was that there is no clear definition of an "assault weapon."

Guns often fell under the ban based on trivial, cosmetic qualities. The addition of a pistol stock to an otherwise legal semi-automatic rifle could make its owner liable to felony prosecution for building an "assault weapon." Likewise, removing a bayonet lug and replacing a threaded flash suppressor with a pinned one could make a banned design legal.

The most popular guns covered by the ban, such as the AR-15, are quite expensive and rarely used in crime. They are popular among recreational and competitive shooters for their high quality, easy customization, and relatively inexpensive ammunition.

I support enforcement of our laws against straw purchases and gun trafficking. I abhor the shameless attempt by antigun media figures, our politicians, and the Mexican government to shift blame for their failures onto the US. Only 17 percent of firearms seized in Mexico have been traced to the United States. Where did the rest come from?

The US needs a carbon tax

Regarding the April 14 article, "Who's going to get the carbon pollution credits?": A carbon tax is much simpler and more effective than cap-and-trade.

It is true that a carbon tax would add to the cost of domestic goods and thus have a decidedly anticompetitive feature. However, the cost impact of a carbon tax on domestic industrial users can be neutralized.